Body mass index and thromboembolism in children with hematological malignancies.

We evaluated the effects of body mass index (BMI) on the risk of thromboembolism (TE) in children (<18 years) with hematological malignancies during the period 1990-2009 (n = 359). Obesity was prevalent in 12% of patients: 6% versus 17% prior to and after the year 2000 (P = 0.02). Sixty-one (17%) patients developed TE; increasing BMI was associated with increased, but statistically insignificant risk of TE [adjusted odds ratios (OR): 0.75 (95%CI 0.32-1.77), 0.93 (95%CI 0.38-2.30), and 1.01(95%CI 0.42-2.41) for underweight, overweight, and obese group]. A large prospective study is needed to define the impact of BMI on the risk of TE in children.